// Verifies that EncodedS2LaxPolygonShape behaves identically to
// S2LaxPolygonShape. Also supports testing that the encoded form is identical
// to the re-encoded form.
private static void TestEncodedS2LaxPolygonShape(S2LaxPolygonShape original)
{
Encoder encoder = new();
original.Encode(encoder, CodingHint.COMPACT);
var decoder = encoder.Decoder();
var(success, encoded) = EncodedS2LaxPolygonShape.Init(decoder);
Assert.True(success);
Assert.Equal(encoded.NumLoops, original.NumLoops);
Assert.Equal(encoded.NumVertices, original.NumVertices);
Assert.Equal(encoded.NumEdges(), original.NumEdges());
Assert.Equal(encoded.NumChains(), original.NumChains());
Assert.Equal(encoded.Dimension(), original.Dimension());
Assert.Equal(encoded.IsEmpty(), original.IsEmpty());
Assert.Equal(encoded.IsFull(), original.IsFull());
Assert.Equal(encoded.GetReferencePoint(), original.GetReferencePoint());
for (int i = 0; i < original.NumLoops; ++i)
{
Assert.Equal(encoded.NumLoopVertices(i), original.NumLoopVertices(i));
Assert.Equal(encoded.GetChain(i), original.GetChain(i));
for (int j = 0; j < original.NumLoopVertices(i); ++j)
{
Assert.Equal(encoded.LoopVertex(i, j), original.LoopVertex(i, j));
Assert.Equal(encoded.ChainEdge(i, j), original.ChainEdge(i, j));
}
}
// Now test all the edges in a random order in order to exercise the cases
// involving prev_loop_.
var count = original.NumEdges();
List <int> edge_ids = new(count);
LinqUtils.Iota(edge_ids, 0, count);
var mt = new PseudoRandom.MersenneTwister();
edge_ids = edge_ids.Shuffle(mt.genrand_N).ToList();
foreach (var e in edge_ids)
{
Assert.Equal(encoded.GetChainPosition(e), original.GetChainPosition(e));
Assert.Equal(encoded.GetEdge(e), original.GetEdge(e));
}
// Let's also test that the encoded form can be encoded, yielding the same
// bytes as the originally encoded form.
Encoder reencoder = new();
encoded.Encode(reencoder, CodingHint.COMPACT);
Assert.True(encoder == reencoder);
}